Adrenergic Agonists Flashcards
What do adrenergic agents do?
Stimulate the sympathetic system
Which does not act on B2 receptors, epinephrine or norepinephrine?
Norepinephrine
What are the 4 adrenergic receptors?
A1
A2
B1
B2
Which adrenergic agonist and % is commonly used in conjunction with Tropicamide in dilation?
Phenylephrine 2.5%
Which receptors does phenylephrine work on?
Alpha 1
-no effect on beta receptors
Which type of adrenergic receptors are found in the ciliary body?
Beta receptors
Why does phenylephrine cause dilation without cycloplegia?
It only works on alpha 1 receptors, and the receptors in the ciliary body are Beta receptors
Which adrenergic agonists can be used to help diagnose Horner’s syndrome?
Phenylephrine
Apraclonidine
Phenylephrine is contraindiacted in persons using what 3 meds?
MAOIs
Tricyclic antidepressants
Atropine
Which adrenergic agonist is contraindicated in patients with Graves disease?
Phenylephrine
What are the 3 non-glaucoma adrenergic agonists?
Phenylephrine
Naphazoline
Tetrahydrozoline
What are naphazoline and tetrahydrozoline typically used for?
Ocular decongestants
Naphazoline and tetrahydrozoline have a greater effect on which receptors?
Alpha more than beta
What are the 2 alpha adrenergic agonists used for glaucoma therapy?
Brimonidine
Apraclonidine
-alpha2 agonists
How do the adrenergic agonists work to treat glaucoma?
Decrease aqueous humor production
Increase uveoscleral outflow
What is the trade name of brimonidine?
Alphagan
Alphagan is highly selective for which receptor?
Alpha 2
Brimonidine (Alphagan) is contraindicated in patients taking what meds?
MAOIs
Which glaucoma med is shown to have a neuroprotective effect?
Brimonidine (Alphagan)
What is the recommended dosing schedule for brimonidine (Alphagan)?
TID
What are the possible side effects of brimonidine?
Miosis
Dry mouth
Which is more alpha 2 selective, brimonidine or apraclonidine?
Brimonidine
Why isn’t apraclonidine used as a chronic glaucoma therapy?
Loses efficacy rapidly - within 8 days (tachyphylaxis)
Long term use has a 50% risk for allergic response
In which lighting conditions will Horner’s anisocoria be more pronounced?
Dark (the sympathetic system is affected)
In a patient with Horner’s, phenylephrine will still give a full dilation if the lesion is where?
Postganglionic
What adrenergic receptors are found in the iris?
Alpha 1
When beta2 receptors in the ciliary body are stimulated, what is the effect on aqueous production?
Increased production
What is the 1 systemic alpha 2 agonist?
Clonidine
What drug is a non-specific alpha and beta agonist?
Pseudoephedrine
What are the systemic beta 2 agonists?
Salmeterol Albuterol Levalbuterol Metproterenol Terbutaline
What is the 1 beta1/2 agonist?
Isoproterenol
